To meet the requirements of different container sizes or the requirements of containers with changeable bottom or wall elements, it is customary in the case of multilevel containers to ensure the stability of the container in the butt joint region by means of an appropriately robustly designed bracing ring (German Patent DE U1 88 10 118). Between the bracing ring and the outwardly beaded end faces of the container wall or bottom elements, elastic sealing rings are inserted into the butt joints. An elastic sealing ring or one of the lips of a multisegmented elastic sealing ring is inserted in the area between the facing end faces of the outwardly beaded sheet metal of which the bottom and wall elements are made. While the bracing ring and the radially outwardly beaded end faces can be in direct contact with each other, the sealing ring between the radially outwardly beaded end faces facing each other, however, cannot be omitted.
To increase the stability along the butt joint, a supporting ring which is located on the inside and which partially straddles the two neighboring container walls can be used (German Patent DE A1 40 09 659).
Multilevel containers made of sheet metal are known in which the butt joints are reinforced with massive flanges. These flanges are welded to the circumference of the container wall. Compared to these known containers, the generic multilevel containers with beaded end faces have the advantage that they can be produced much less expensively.
To provide the butt joints of this design with sufficient stability, however, the conventionally known beaded areas are reinforced in a bridge-like manner by means of multiple beads in alternating directions. Among other things, these reinforcements have the disadvantage that they form grooves in which the material stored in the container can be trapped. For reasons of hygiene, this is undesirable, especially in food and pharmaceutical applications.